2022 to 1965: Looking Back and Looking Forwards

Click on the image for a larger version. The front page of a 1965 White House Report.

Friends, last week I wrote about the curious perspective that I gained in reading a Scientific American article on global warming from 1978 (link).

After reading that article, a friend sent me a link to a 1965 White House Report on Environmental  Pollution. You can download a copy here.

The report covered many topics, and tucked away in Appendix Y4 (a sub-appendix of Appendix X6 on “Air Problems”), was an analysis of Atmospheric Carbon Dioxide pollution.

Click on the image for a larger version. The appendices of a 1965 White House Report.

Appendix Y4 begins with a section entitled:

Carbon Dioxide from Fossil Fuels – The Invisible Pollutant

This article is a précis of the report and is followed by a reflection on the document’s conclusions from our perspective in 2022.

Précis#1: How much CO2 are we emitting?

The article begins by outlining the role of CO2 in controlling Earth’s climate. It then goes on to estimate the amount of CO2 in the atmosphere and the rate at which it is increasing from burning of fossil fuels. This exposition is well-written and overall very similar to our modern conception.

The Report goes on to make guesstimates of the likely atmospheric concentration in the years leading up to 2009.

In Table 6, it suggests that if there is no growth in the rate of fossil fuel emission, then in 2009 atmospheric emissions of CO2 would be 31% higher than in 1950. Assuming that 50% of these emissions ended up in the atmosphere (rather than the oceans or the biosphere) then atmospheric CO2 concentration in 2009 would be approximately 346 ppm. This estimate is shown in the figure below.

Click on the image for a larger version. The atmospheric concentration of CO2 at the Mauna Loa Observatory – the so-called Keeling Curve. Also shown is the date of the report and two predictions for the atmospheric concentration assuming either no growth in fossil fuel use, or growth at 3.2% p.a.

Table 6 also included predictions for higher growth rates in fossil fuel use (3.2% p.a. and 5.0 % p.a.) that result in predicted concentrations in 2009 of 386 ppm (close to what was observed) and 440 ppm. This latter prediction is just off the chart above, and we will probably reach this concentration in about 2030.

Précis#2: The effect on Earth’s temperature: looking forward.

When considering the likely effect of a 25% increase in atmospheric concentrations the report highlights (then) recent calculations suggesting that the warming would be between 0.6 °C and 4 °C “depending on the behaviour of water vapour“.

The report goes on to point out that there is more water vapour in the atmosphere near the Equator (because it is warmer) than near the poles (where it is colder). In contrast, CO2 is (after a few years of mixing) distributed uniformly around the globe.

Since both water vapour and CO2 are greenhouse gases, the comparative effect of the CO2 (wrt to water vapour) was likely to be more significant at higher latitudes.

However the general conclusion of the report was that more complex calculations were required, and these would likely be complete in the next two to three years i.e. by the end of the 1960’s.

Précis#3: The effect on Earth’s temperature: looking back.

The report also considered the experimental evidence that CO2 emissions of the previous century had already warmed the Earth.

Click on the image for a larger version. The Estimate of Global Average Temperature over the period 1850 to 2018. Also shown is the date of the report. We now know that the rate of warming  over the previous 30 was anomalously stable, but that there had been warming episodes earlier in the Century, and – although they did not know it – profound and ongoing warming was to follow for the following 55 years.

The report noted the work of Callendar (précis here) in 1937 who pointed out (correctly) that the Earth’s temperature had risen since the 1880s, and that the rise in atmospheric CO2 was a likely culprit.

However, they considered that Callendar had likely overestimated the rise in atmospheric CO2, and that the observed world-wide rise in temperature (which they confirmed) probably could not wholly be caused by CO2.

They then noted (correctly) that the Earth’s temperature had not risen substantially in the preceding 30 years (i.e. 1935 to 1965) during which CO2 emissions had risen by 40%.

Overall they concluded that climatic “noise” – intrinsic variability – had masked the warming – which implied that CO2-induced warming was not a significant problem at the present moment.

Précis#4: Other effects.

The report also considered other possible effects of increased concentrations of atmospheric CO2.

• Melting of the Antarctic Ice Cap
• Rise of sea level
• Warming of sea water
• Increased acidity of fresh water
• Increase in photosynthesis

All the effects were considered potentially very significant, but at the time there was little evidence of harm in the near term.

It also considered other possible sources of increased concentrations of atmospheric CO2 aside from fossil fuels.

• Oceanic warming
• Cement production
• Soil degradation
• Ocean organic matter
• Decline in capture rate of CO2 by the deep ocean
• Changes in the volume of sea water
• Volcanoes
• Balance of dissolution and precipitation of carbonates.

But overwhelmingly they considered (correctly) that fossil fuel burning was the major source of atmospheric CO2 .

Précis#5: Conclusions.

The first few paragraphs of the Report’s conclusions summarise the report with admirable brevity.

Click on the image for a larger version. The first few paragraphs of the conclusions.

This summary contains two key sentences:

The first sentence states that (using gender neutral terminology):

Through worldwide industrial civilisation, humanity is unwittingly conducting a vast geophysical experiment.

Then the last sentence states:

The climatic changes that may be produced by the increased CO2 content could be deleterious from the point of view of human beings.

So having identified a potentially profound  problem what did this committee recommend?

Shockingly, their only comments were on albedo modification – cooling the Earth  by making it more reflective – by adding either white balls to the ocean surface, or seeding cirrus clouds.

And it is this response that I want to conclude on.

What can we learn by looking at this report?

So back in 1965 the brightest and the best – including Dr. Keeling of the Keeling Curve – looked at this issue, and with no strong evidence of the ongoing effect of CO2 (the temperature had not risen noticeably in the previous 30 years) and no ability to calculate the likely effect (such calculations would be 2 or 3 years off) concluded that if this became a problem in later years, all we could do was to alter the albedo of the Earth.

I think this gives us a really profound insight into the zeitgeist of the time. This group considered that there was literally no alternative to burning fossil fuels – it was central to industrial society.

The contrast with what is happening today is stark.

Appendix Y4 of the report is essentially an early version of the current IPCC report. Except that:

• Now we have climate models that allow us to understand the role of CO2 in exceptional – but still not perfect – detail.
• Now we have data that allow us to understand the role of the CO2 in affecting our climate over decades, centuries and millennia
• Now we would suggest fossil-fuel demand reduction strategies: insulation of homes and targets for improved mileage on motor vehicles.
• Now we would suggest increased use of solar and wind power – the cheapest and fastest growing technologies for electricity generation.
• Now we would suggest increased use of internet-enabled grid-scale batteries which can stabilise the grid over seconds, minutes and hours.
• Now we would  suggest development of longer term storage options to keep the grid operational over hours, days and weeks.
• Now we would suggest increased nuclear power.
• Now we would suggest a switch to electrically-powered vehicles.

In short, now we have access to technologies that did not exist in 1965, and which did not exist at a global scale until just a few years ago.

So although it would have been better to have started earlier, as I have written previously – I don’t think we are as far behind the optimal curve as it may seem.